What should come in place of the question mark (?) in the given series?
24, 30, 25, 29, 26, ?

Given: 24, 30, 25, 29, 26, ?

Logic: Odd positions increasing by + 1 and even positions decreasing by - 1 place.

Odd positions:

24, 25, 26 → increasing by + 1

Even positions:
30, 29, ? → decreasing by - 1

Continue the even-position pattern

30 → 29 → 28

So, the missing term is 28.

Thus, correct option is (a).